Named after Ulysses S. Grant, the Civil War general and later president.
The community was originally known as Frenchtown. Sources differ on when it was renamed: Wikipedia says soon after the Civil War began; Forgotten New York says after the war, when the engineer John Thompson built it up and named it for the sitting president. Either way, it went against local feeling: the war was so unpopular on Staten Island that anti-draft riots broke out in July 1863.